Parametric linear bushing with low-friction (POM/delrin/nylon) filament inserts

thingiverse

This is a fully customizable linear bushing created with OpenSCAD code that features a low-friction interface made possible by inserts of ultra-low friction filament. The sliding interface consists of four sections of filament that spiral 90 degrees in order to provide sturdy 4-point support and prevent uneven wear on the rods. The body of the bushing can be printed on any material; I've successfully used PLA for the body and POM for the sliding interface. I previously tested with 1.75 mm POM filament inserts, which have been sliding smoothly on my carbon fiber tubes for nearly eight months (see my original design: https://www.thingiverse.com/thing:2834026). In this version, I modified my original solution to make it more universal and adaptable to the LMXUU kind of bushings or any size you prefer. To create your own custom bushing, simply open the provided .scad file in OpenSCAD and set the diameter and length values as needed. Then, cut small segments of 1.75 mm low-friction filament (POM, acetal, nylon, igus, etc) and insert them into the four slots. Adjusting the bushing to your axes may require some trial and error, as you'll need to tweak the variables 'clearance' and 'fildia' to fine-tune the fit. One effective method for achieving a smooth fit is to pass a heated rod quickly through an assembled bushing, which will create a tight and virtually play-free connection. While I haven't tested these bushings on other materials besides carbon fiber, I assume they should work well with any material where Igus bushings are known to function. I have included standard values for reference in the code comments, so feel free to experiment and adjust the parameters as needed. With a little patience and some trial-and-error tweaking, you'll be able to create your own custom linear bushing that meets your specific requirements.